Becoming pescatarian means cutting out meat and poultry while keeping fish, seafood, eggs, and dairy in your diet. It’s one of the simpler dietary shifts to make because you’re replacing one protein category (land animals) with another (seafood) rather than eliminating animal protein entirely. The transition works best when you approach it in stages rather than overhauling your kitchen overnight.
What You Eat and What You Don’t
A pescatarian diet excludes beef, pork, chicken, turkey, lamb, and any other land-animal meat. Everything else is on the table: all types of fish, shellfish, eggs, dairy, vegetables, fruits, grains, legumes, nuts, and seeds. This makes it more flexible than vegetarian or vegan diets, especially when eating out or traveling, since most restaurants offer at least one seafood option.
The seafood category is broad. You can eat fin fish like salmon, cod, tilapia, and tuna, along with shellfish like shrimp, mussels, clams, crab, and oysters. Some pescatarians lean heavily on fish while others eat it just a few times a week, filling the rest of their meals with plant-based proteins like lentils, beans, and tofu. There’s no single “correct” version of the diet.
A Practical Transition Plan
The easiest approach is to phase out meat over two to four weeks rather than quitting all at once. Start by identifying the meals where you already don’t eat meat. Breakfast might already be eggs or oatmeal. Lunch might already be a salad or grain bowl. For many people, dinner is the only meal that regularly features chicken or beef, which means you really only need to rethink one meal a day.
During week one, swap meat for fish in two or three dinners. A piece of baked salmon where you’d normally have chicken, shrimp stir-fry instead of beef, or fish tacos instead of ground turkey. During week two, replace the remaining meat dinners with either seafood or plant-based meals like lentil soup, black bean burritos, or pasta with marinara. By week three, meat is simply no longer in your rotation.
Stock your pantry with canned tuna, canned salmon, sardines, frozen shrimp, dried lentils, canned beans, eggs, and cheese. These are the building blocks of quick pescatarian meals, and having them on hand prevents the moment where you’re hungry, unprepared, and tempted to default back to a chicken breast.
Getting Enough Protein
Protein is the nutrient people worry about most when cutting meat, but seafood is a direct swap. A three-ounce serving of fish (roughly the size of a deck of cards) provides about 21 grams of protein, which is comparable to the same portion of chicken or beef. Two meals a day containing fish, eggs, or legumes will easily meet most adults’ protein needs.
On days when you don’t eat seafood, legumes carry the load. A half cup of lentils has 9 grams of protein. The same amount of black beans or kidney beans has about 8 grams. Combine those with rice, whole-grain bread, or eggs, and you’re hitting solid protein numbers without any fish at all. Greek yogurt, cottage cheese, nuts, and seeds fill in the gaps.
Nutrients to Pay Attention To
The two nutrients that require the most attention on a pescatarian diet are iron and vitamin B12. Red meat is a major source of both in a standard diet, so removing it means you need to be intentional about replacements.
For iron, your best seafood sources are oysters, mussels, shrimp, and sardines. Plant sources include spinach, lentils, chickpeas, fortified cereals, quinoa, and pumpkin seeds. Iron from plant foods is harder for your body to absorb, but eating it alongside something rich in vitamin C (citrus, tomatoes, bell peppers) significantly improves absorption.
Vitamin B12 is easier on a pescatarian diet than on a vegetarian one because fish and shellfish are excellent sources. Salmon, trout, clams, and crab all provide B12, as do eggs, milk, yogurt, and cheese. If you eat seafood or dairy regularly, B12 deficiency is unlikely. Nutritional yeast is another option, as some brands are fortified with B12.
Omega-3 Fatty Acids
One of the clear advantages of a pescatarian diet is a higher intake of omega-3 fatty acids, the anti-inflammatory fats found in oily fish. Salmon, mackerel, sardines, herring, and trout are especially rich sources. There’s no universally agreed-upon daily target for omega-3s in healthy adults, but the American Heart Association recommends eating fatty fish at least twice a week. For people with existing heart disease, the recommendation is roughly 1 gram per day of the two key omega-3s found in fish, ideally from food rather than supplements.
Heart Health and Other Benefits
A large study published in The BMJ found that pescatarians had a 13% lower risk of ischemic heart disease (the type caused by reduced blood flow to the heart) compared to meat eaters. That benefit likely comes from the combination of higher omega-3 intake, lower saturated fat consumption, and greater intake of fiber and antioxidants from the plant-heavy portions of the diet.
Pescatarian diets also tend to be lower in calories and higher in micronutrients than standard Western diets, which can make weight management easier without deliberate calorie counting. The high protein content of fish and legumes helps with satiety, meaning you feel full longer after meals.
Environmental Impact
If environmental concerns are part of your motivation, the data is encouraging. A study covered by Yale Environment 360 found that pescatarian diets produce less greenhouse gas, less water pollution, and use less land than even low-meat diets (those with 50 grams or less of meat daily). Vegetarian and vegan diets do perform slightly better, but the differences between pescatarian and vegetarian diets are small. Going pescatarian gets you most of the environmental benefit without fully eliminating animal protein.
Choosing sustainably sourced seafood amplifies this benefit. Look for certifications from the Marine Stewardship Council (MSC) on wild-caught fish or the Aquaculture Stewardship Council (ASC) on farmed fish. Smaller fish like sardines, anchovies, and mackerel tend to have lower environmental footprints than large predatory species.
Mercury: What to Know
Mercury in seafood is a legitimate concern, but it’s manageable with basic awareness. The FDA classifies fish into three tiers based on mercury content. The “Best Choices” category, which includes salmon, shrimp, cod, tilapia, sardines, and trout, is safe to eat two to three servings per week. “Good Choices” like halibut, snapper, and yellowfin tuna should be limited to one serving per week.
A small number of fish fall into the “Choices to Avoid” category due to high mercury levels: king mackerel, marlin, shark, swordfish, orange roughy, Gulf of Mexico tilefish, and bigeye tuna. These are species worth skipping entirely or eating very rarely, especially if you’re pregnant or breastfeeding. For most people eating standard supermarket fish like salmon, shrimp, and cod, mercury exposure stays well within safe limits.
Making It Stick
The most common reason people abandon a new diet is boredom, not difficulty. Build variety into your routine from the start. Rotate between different types of fish (salmon one night, shrimp the next, canned tuna for lunch), and make sure at least a couple of dinners each week are entirely plant-based so you’re not relying on seafood for every single meal.
Learn a handful of versatile sauces and seasonings. A piece of white fish can taste completely different depending on whether you top it with salsa verde, a soy-ginger glaze, or lemon butter. Similarly, a base of rice and beans transforms depending on the cuisine: Cuban black beans one night, Indian dal the next, Mexican refried beans another. The underlying structure of your meals stays simple while the flavors keep shifting.
Eating out is rarely a problem. Most restaurants offer at least one fish entree, and many cuisines naturally feature seafood-heavy dishes: Japanese, Mediterranean, Thai, and Peruvian food all work well. At burger joints or steakhouses, look for fish sandwiches, shrimp plates, or hearty salads. The flexibility of the pescatarian approach means social meals don’t require special accommodations or awkward substitutions.